3A,4,6,7-Tetrahydro-3-phenyl-7-(phenylalkylene)-thiopyrano[4,3-C]pyrazole-2(3H)-alkanamine, and analogs

ABSTRACT

Anti-inflammatory activity and hypotensive activity are exhibited by compounds having the formula ##SPC1## 
     The salts thereof, and the 5-oxide and 5,5-dioxide thereof, wherein A is a straight or branched chain alkylene group; R 1  is hydrogen, alkyl, alkoxy, trifluoromethyl, or halogen; R 2  is hydrogen or alkyl; and R 3  is hydrogen, alkyl, phenyl, or phenylalkyl.

BRIEF DESCRIPTION OF THE INVENTION

Compounds having the formula ##SPC2##

The 5-oxide and 5,5-dioxide thereof, and the pharmaceutically acceptable acid addition and quaternary ammonium salts thereof, have useful pharmacological activities, and can be used in mammals to treat inflammation and to lower blood pressure. In formula I, and throughout the specification, the symbols are as defined below.

A can be a straight or branched chain alkylene group having 2 to 5 carbon atoms;

R₁ can be hydrogen, alkyl, alkoxy, trifluoromethyl, or halogen;

R₂ can be hydrogen or alkyl; and

R₃ can be hydrogen, alkyl, phenyl, or phenylalkyl.

The terms alkyl and alkoxy, as used throughout the specification, refer to groups having 1 to 8 carbon atoms. Alkyl and alkoxy groups having 1 to 3 carbon atoms are preferred.

The term phenylalkyl, as used throughout the specification, refers to groups of the formula ##SPC3##

Wherein alkyl is as defined above. Benzyl and phenethyl are the preferred phenylalkyl groups.

The term halogen, as used throughout the specification, refers to fluorine, chlorine, bromine, and iodine; fluorine and chlorine are preferred.

DETAILED DESCRIPTION OF THE INVENTION

The compounds of formula I (and the 5-oxides and 5,5-dioxides thereof) are prepared using as starting materials a substituted tetrahydro-4H-thiopyran-4-one having the formula ##SPC4##

Or a 1-oxide or 1,1-dioxide thereof, and a hydrazine having the formula

    III H.sub.2 NNH--A--NR.sub.2 R.sub.3.

The compounds of formulas II and III are readily obtainable; see, for example, Journal of the American Chemical Society, 79:156 (1957) and Journal of Medicinal Chemistry, 7:493 (1964).

A substituted tetrahydro-4H-thiopyran-4-one of formula II can be prepared by reacting tetrahydro-4H-thiopyran-4-one with an appropriate benzaldehyde having the formula ##SPC5##

The corresponding 1-oxide or 1,1-dioxide can be prepared by reacting a substituted tetrahydro-4H-thiopyran-4-one of formula II with an appropriate amount of an oxidizing agent; sodium periodate is preferred for preparing a 1-oxide and hydrogen peroxide is preferred for preparing a 1,1-dioxide.

A hydrazine of formula III can be prepared by reacting an excess of hydrazine (H₂ NNH₂) with a haloamine having the formula

    V X--A--NR.sub.2 R.sub.3,

wherein X is chlorine or bromine.

Reaction of a substituted tetrahydro-4H-thiopyran-4-one of formula II (or a 1-oxide or 1,1-dioxide thereof) with a hydrazine of formula V yields a product of formula I, or the corresponding 5-oxide or 5,5-dioxide. The reaction can be run in an organic solvent, preferably a lower alkanol such as methanol. While reaction conditions are not critical, the reaction will preferably be run at, or near, the reflux temperature of the solvent.

Alternatively, the compounds of formula I can be obtained by first reacting a substituted tetrahydro-4H-thiopyran-4-one of formula II with a hydroxyalkyl hydrazine having the formula

    VI H.sub.2 NNH--A--OH

to form an intermediate having the formula ##SPC6##

An alcohol of formula VII can be reacted with an alkylsulfonyl or arylsulfonyl halide, preferably p-toluenesulfonyl halide, to yield a compound of the formula ##SPC7##

wherein Y is alkyl or aryl. The intermediate of formula VIII can be treated with an amine having the formula

    IX HNR.sub.2 R.sub.3

to yield the products of formula I. This method is particularly useful in preparing those compounds of formula I wherein R₂ and R₃ are both hydrogen.

The 5-oxide and 5,5-dioxide derivatives of a compound of formula I can, alternatively, be prepared by oxidizing the corresponding 3a,4,6,7-tetrahydro-3-phenyl-7-(phenylalkylene)thiopyrano[4,3-c]pyrazole-2(3H)-alkanamine of formula I. Oxidation of a compound of formula I using one equivalent of sodium periodate or hydrogen peroxide yields the corresponding sulfoxide derivative. Oxidation of a compound of formula I using potassium permanganate or excess hydrogen peroxide yields the corresponding sulfonyl derivative. Alternatively, the sulfoxide and sulfonyl derivatives can be prepared by treating compounds of formula I with m-chloroperbenzoic acid. Treating a compound of formula I with an equivalent of m-chloroperbenzoic acid for from 2 to 24 hours at room temperature yields the corresponding sulfoxide derivative. Treating a compound of formula I, or a sulfoxide derivative of a compound of formula I, with two equivalents of m-chloroperbenzoic acid for 2 to 24 hours at room temperature (or for a shorter time with slight heating) yields the corresponding sulfonyl derivative.

The compounds of formula I form acid addition salts with inorganic and organic acids. These acid addition salts frequently provide useful means for isolating the products from reaction mixtures by forming the salt in a medium in which it is insoluble. The free base may then be obtained by neutralization, e.g., with a base such as sodium hydroxide. Any other salt may then be formed from the free base and the appropriate inorganic or organic acid. Illustrative are the hydrohalides, especially the hydrochloride and hydrobromide which are preferred, sulfate, nitrate, phosphate, borate, acetate, tartrate, maleate, citrate, succinate, benzoate, ascorbate, salicylate, methanesulfonate, benzenesulfonate, toluenesulfonate and the like.

The compounds of formula I form quaternary ammonium salts with alkyl halides (e.g., methyl chloride, isobutyl bromide, dodecyl chloride and cetyl iodide), benzyl halides (e.g., benzyl chloride), and dialkyl sulfates (e.g., dimethyl sulfate).

The componds of formula I, the pharmaceutically acceptable acid addition salts thereof, the quaternary ammonium salts thereof, and the 5-oxide and 5,5-dioxide thereof, are useful in treating inflammation in mammalian species, e.g., rats, dogs, cats, monkeys, etc. Joint tenderness and stiffness (in conditions such as rheumatoid arthritis) are relieved by the above described compounds.

Additionally, the compounds of formula I, the pharmaceutically acceptable acid addition salts thereof, the quaternary ammonium salts thereof, and the 5-oxide and 5,5-dioxide thereof, are useful in lowering blood pressure in mammalian species.

The compounds of this invention can be formulated for use as anti-inflammatory agents and hypotensive agents according to accepted pharmaceutical practice in oral dosage forms such as tablets, capsules, elixirs, or powders, or in an injectable form in a sterile aqueous vehicle prepared according to conventional pharmaceutical practice. The compounds of this invention may be administered in amounts of 100 mg/70kg/day to 2 g/70kg/day, preferably 100 mg/70kg/day to 1 g/70kg/day.

The following examples are specific embodiments of this invention.

EXAMPLE 1 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine

Tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one (5g) is refluxed with 2.1g of 3-dimethylaminopropylhydrazine in 50ml of methanol for 4 hours. The solvent is evaporated off and the residue is crystallized from 30ml of acetonitrile to yield 3.9g of the title compound, melting point 83°-85°C.

EXAMPLE 2 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine, maleate

3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine (3.7g, prepared as described in Example 1) and 1.1g of maleic acid are dissolved in 30ml of warm acetonitrile and diluted with 100ml of ether. After cooling for about 16 hours, the material is filtered, washed with ether, and dried in vacuo. The material is crystallized from methanol-ether (3:20) yielding 4.2g of the title salt, melting point 147°-149°C.

EXAMPLE 3 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5-oxide

A. Tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one, 1-oxide

A solution of 10.4g of sodium periodate in 50ml of water is added to a suspension of 7.0g of tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one in 300ml of methanol. The mixture is stirred at room temperature for 3 days (a water bath is used for the first hour to moderate a slightly exothermic reaction). Solvent is removed in vacuo and the residue is stirred with chloroform and filtered. The filtrate is concentrated in vacuo and the residue is crystallized from 150ml of methanol, giving 6.4g of the title compound, melting point 155°-160°C. A second crop of 0.5g of the title compound, melting point 154°-157°C is also obtained.

B. 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2-(3H)-propanamine, 5-oxide (two isomers)

A stirred mixture of 2.5g of tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one, 1-oxide and 0.95g of 3-dimethylaminopropylhydrazine in 75ml of methanol is heated and the resulting solution is refluxed for 5 hours. After standing overnight at room temperature, the methanol is removed on a rotary evaporator and the residue is triturated with 100ml of boiling isopropyl ether to yield a solid, which after cooling weighs 2.0g, melting point 138°-140°C.

Thin layer chromatography (ethyl acetate on alumina) shows a mixture of compounds is present. Crystallization from 10ml of acetonitrile yields 0.9g of material, melting point 153°-155°C. (TLC: single spot; ethyl acetate on alumina R_(f) 0.38). The acetonitrile liquor is evaporated and the residue is dissolved in 4ml of acetonitrile. Cooling overnight yields 0.15g of material, melting point 125°-127°C (TLC: essentially single spot; ethyl acetate on alumina, R_(f) 0.31; small amount of material with R_(f) 0.38 present).

EXAMPLE 4 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide

Tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one, 1,1-dioxide (4.9g, prepared as described in Journal of American Chemical Society, 79:156 (1957)) is reacted with 1.8g of 3-dimethylaminopropylhydrazine in 200 ml of methanol for 4 hours. The solvent is evaporated off and the residue is extracted with 400ml of boiling isopropyl ether, leaving 2.3g of material undissolved. The extract is filtered through glass wool and concentrated to 150ml; the title compound separates. After cooling for 72 hours, the material is filtered, washed with isopropyl ether and dried in vacuo to yield 3.5g of the title compound, melting point 127°-129°C.

EXAMPLE 5 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide, hydrochloride (1:1)

3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide (3.4g) is dissolved in 25ml of warm methyl ethyl ketone, cooled and treated with 1.35ml of 6.1N alcoholic hydrogen chloride. On seeding and rubbing, the crystalline hydrogen chloride salt separates. Ether is added to complete the precipitation and after cooling for about 16 hours the solid is filtered, washed with ether and dried in vacuo to give 3.5g of material, melting point 183°-185°C. Following crystallization from 20ml of methanol-40ml of ether, there remains 2.6g of the title compound, melting point 192°-194°C.

EXAMPLE 6 3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanamine

A. 3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanol

Following the procedure of Example 1, but substituting (2-hydroxyethyl)hydrazine for 3-dimethylaminopropylhydrazine, yields the title compound.

B. 3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanamine

3a,4,6,7-Tetrahydro-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-ethanol is suspended in pyridine and treated with one equivalent of tosyl chloride. After standing at room temperature for about 16 hours, the mixture is poured into water and the tosylate is dissolved in ethanol, cooled and saturated with ammonia gas. After standing for 3 days, the excess ammonia and solvent are removed by evaporation to give the title compound.

EXAMPLE 7 3a,4,6,7-Tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine, methochloride

A solution of 3.0g of 3a,4,6,7-tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine (from Example 1) in 30ml in acetonitrile is cooled and treated with 5.0g of methyl chloride gas. The resulting solution is allowed to stand at room temperature for a day and the solvent is evaporated to give the title compound.

EXAMPLES 8-14

Following the procedure of Example 1, but substituting the compound listed in column I for tetrahydro-3,5-bis-(phenylmethylene)-4H-thiopyran-4-one and the compound listed in column II for 3-dimethylaminopropylhydrazine, yields the compound listed in column III.

    __________________________________________________________________________     Example                                                                             Column I           Column II        Column III                            __________________________________________________________________________      8   tetrahydro-3,5-bis-[(2-methyl-                                                                    methylaminopropylhydrazine                                                                      3a,4,6,7-tetrahydro-N-methyl-3-(2                                              -                                          phenyl)methylene]-4H-thiopyran-     methylphenyl)-7-[(2-methylphenyl)                                              -                                          4-one                               methylene]thiopyrano[4,3-c]pyrazo                                              le-                                                                            2(3H)-propanamine                      9   tetrahydro-3,5-bis-[(4-methoxy-                                                                   N-benzyl-N-methylaminoethyl-                                                                    3a,4,6,7-tetrahydro-N-benzyl-N-            phenyl)methylene]4H-thiopyran-                                                                    hydrazine        methyl-3-(4-methoxyphenyl)-7-              4-one                               [(4-methoxyphenyl)methylene]thio-                                              pyrano[4,3-c]pyrazole-2-(3H)-etha                                              na-                                                                            mine                                  10   tetrahydro-3,5-bis-[(4-trifluoro-                                                                 N-methyl-N-phenylaminopentyl-                                                                   3a,4,6,7-tetrahydro-N-methyl-N-            methylphenyl)methylene]-4H-thio-                                                                  hydrazine        phenyl-3-(4-trifluoromethylphenyl                                              )-                                         pyran-4-one                         7-[(4-trifluoromethylphenyl)methy                                              l-                                                                             ene]thiopyrano[4,3-c]pyrazole-2(3                                              H)-                                                                            pentanamine                           11   tetrahydro-3,5-bis-[(2-chloro-                                                                    (2-aminoethyl)hydrazine                                                                         3a,4,6,7-tetrahydro-3-(2-chloro-           phenyl)methylene]-4H-thiopyran-     phenyl)-7-[2-(chlorophenyl)methyl                                              ene]-                                      4-one                               thiopyrano[4,3-c]pyrazole-2(3H)-                                               ethanamine                            12   tetrahydro-3,5-bis-(phenylmethyl-                                                                 phenylaminopropylhydrazine                                                                      3a,4,6,7-tetrahydro-N-phenyl-3-ph                                              enyl-                                      ene)-4H-thiopyran-4-one             7-(phenylmethylene)thiopyrano[4,3                                              -c]-                                                                           pyrazole-2(3H)-propanamine            13   tetrahydro-3,5-bis-(phenylmethyl-                                                                 benzylaminopropylhydrazine                                                                      3a,4,6,7-tetrahydro-N-benzyl-3-ph                                              enyl-                                      ene)-4H-thiopyran-4-one             7-(phenylmethylene)thiopyrano[4,3                                              -c]-                                                                           pyrazole-2(3H)-propanamine            14   tetrahydro-3,5-bis-[(4-propoxy-                                                                   3-(dimethylamino)-2-methyl-                                                                     3a,4,6,7-tetrahydro-N,N,β-tr                                              imethyl-3-                                 phenyl)methylene]-4H-thiopyran-                                                                   propylhydrazine  (4-propoxyphenyl)-7-[(4-propoxyph                                              enyl)-                                     4-one                               methylene]thiopyrano[4,3-c]pyrazo                                              le-                                                                            2(3H)-propanamine.                    __________________________________________________________________________ 

What is claimed is:
 1. A compound having the formula ##SPC8##a pharmaceutically acceptable acid addition salt thereof, a quaternary ammonium salt thereof, or a 5-oxide or 5,5-dioxide thereof, wherein A is a straight or branched chain alkylene group having 2 to 5 carbon atoms; R₁ is hydrogen, alkyl, alkoxy, trifluoromethyl, or halogen; R₂ is hydrogen or alkyl; and R₃ is hydrogen, alkyl, phenyl, or phenylalkyl; wherein alkyl and alkoxy refer to groups having 1 to 8 carbon atoms.
 2. A compound in accordance with claim 1 wherein A is --CH₂ --CH₂ -- or --CH₂ --CH₂ --CH₂ --.
 3. A compound in accordance with claim 1 wherein A is --CH₂ --CH₂ --CH₂ --.
 4. A compound in accordance with claim 1 wherein R₁ is hydrogen.
 5. A compound in accordance with claim 1 wherein R₁ is hydrogen and R₃ is alkyl.
 6. A compound in accordance with claim 1 wherein R₂ and R₃ are both alkyl.
 7. The compound in accordance with claim 1 having the name 3a,4,6,7-tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine.
 8. The compound in accordance with claim 1 having the name 3a,4,6,7-tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine, maleate.
 9. The compound in accordance with claim 1 having the name 3a,4,6,7-tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5-oxide.
 10. The compound in accordance with claim 1 having the name 3a,4,6,7-tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide.
 11. The compound in accordance with claim 1 having the name 3a,4,6,7-tetrahydro-N,N-dimethyl-3-phenyl-7-(phenylmethylene)thiopyrano[4,3-c]pyrazole-2(3H)-propanamine-5,5-dioxide, hydrochloride. 